When I had my XR4, my fastest prop on my SS was a 31 Triton, followed by a Ron Hill tweaked 30 small ear. The small ear came onto a plane a bit better and was only 1/2 mph slower, which could be day to day variation.
It's interesting to me that some of you run big ear choppers. I tried two big ears when I had the XR4, and although I didn't wash the sides of the boat, the bow was always moving a bit. My boat never ran on a string with big ear choppers.
Now I've got a 225 PM, with a freshly worked gearcase, so I'll be testing this summer. 31 Triton, 30 Triton, 30 small ear, 29 SRX, 28 Dunamis, 26 Trophy...I don't need to buy any more props this year, lots to try.